Lab 3: Simple ns-2 Scripts

3. Set up a ns-2 simulation with specification as follows:

• 4 nodes, n0, n1, n2, and n3
  
• 3 links, connecting (n0 and n2), (n1 and n2), and (n2 and n3)
  
• each link with bandwidth 5Mb, delay 2ms, and RED queue
  
• 1 TCP connection with source at n0 and destination at n3
  
• 1 FTP source attached to n0
  
• the FTP source starting at time 1.2 second
  
• terminate the simulation at 3 second

Creating lab3.tcl

# Creating the core event scheduler/simulator
... FILL IN ...

# Creating 4 nodes
... FILL IN ...

# Outputs nam traces
set nf [open out.nam w]
$ns namtrace-all $nf

# Creating 3 links
# Connecting  node 0 and 2
# Connecting  node 1 and 2
# Connecting  node 2 and 3
# All with bandwidth 5Mb, delay 2ms, and RED queue
... FILL IN ...

# link orientation, for nam display purpose only
$ns duplex-link-op $n0 $n2 orient right-up
$ns duplex-link-op $n1 $n2 orient right-down
$ns duplex-link-op $n2 $n3 orient right

# Create a TCP connection from node 0 to node 3
... FILL IN ...


# Create an FTP source and attach it to the TCP connection
... FILL IN ...


# Schedule events to happen
... FILL IN ...

# A finish proc to flush traces and out call nam
proc finish {} {
        global ns nf
        $ns flush-trace
        close $nf

        puts "running nam..."
        exec nam out.nam &
        exit 0
}

# Start the event scheduler
... FILL IN ...
 
  

prompt> ns lab3.tcl

References:

• The main VINT/ns page
• The ns Manual page